DESCRIPTION (Verbatim from the Applicant's Abstract). The development of Integrated-circuit x-ray Pixel Array Detectors (PAD) is proposed to enhance macromolecular crystallographic data collection at synchrotron sources. Data collection time can be reduced by a factor of 40 with improved data quality. Our ultimate aim is to design and fabricate a PAD having 2000 x 2000 pixels of 150 micrometers x 150 micrometers which can: 1) Collect a set of monochromatic data (90 degree rotation) in 18 seconds using a standard method (0.5 degrees per frame, with an exposure of 100 ms per frame). 2) Collect a set of fine slice data in 90 seconds with a rotation of 0.05 degrees per frame and with an exposure of 50 ms per frame. 3) Collect up to 8 successive frames for time resolved protein crystallography using Laue diffraction. Our aim in Phase I is to test prototypes of 16 x 16 pixel PAD, one analog (APAD), the other digital (DPAD), in order to select the best approach to build a large commercial positioned detector in Phase II. Both types will reduce the time loss for the readout process to almost nothing. These 16 x 16 pixel prototypes will be redesigned in a radiation tolerant layout and re-tested. A decision will then be made between APAD and DPAD or mixed approach. Then a medium scale (50 x 50 or 100 x 100 pixel) modular detector will be fabricated. In Phase II we will put the finishing touches to the design of a modular medium scale array and assemble a large 2000 x 2000 pixel array detector for scientific testing. In Phase III we will build a totally commercial version that would meet all the acceptance, UL, and CE testings. Phase III will also include cost and marketing studies. PROPOSED COMMERCIAL APPLICATION: NOT AVAILABLE